The central focus of the Cytogenetics Core (CYT) is to provide high quality cytogenetic and molecular cytogenetic analysis of human and animal model research samples. The CYT provides specialized services to members of the Mayo Clinic Cancer Center (MCCC) and other investigators within the Mayo research community. Services include: Cell Culture, Routine Chromosome Analysis, DNA and RNA fluorescence in situ Hybridization (FISH), Spectral Karyotyping (SKY) Analysis of human and mouse metaphases, and Custom DNA Probe Production. The service line has recently been enhanced through the development of an RNA FISH Probe Production line and a Tyramide Signal Amplification (TSA) protocol. Together, with the investigator, the CYT assists in determining how these techniques can be utilized to meet the evolving needs of their research studies. The CYT then assists in the translation of these novel assays toward employment as clinical diagnostic tests and prognostic markers of disease, as relevant. In addition to the test menu described above, the CYT staff also provides specialized training to investigators for FISH set-up, and microscope use in an effort to minimize investigator cost and economize technologist time. The technologists that make up the CYT have over 70 years of combined cytogenetic expertise. The CYT has a total of 99 users for this grant cycle, representing 10 of the 10 Cancer Center programs active at the time. Among our 99 users, 73 (74%) are Cancer Center members. Of these 73 investigators, 50 (68%) have active peer-reviewed funding. Many MCCC scientists at the forefront of genetic cancer research require both conventional and molecular cytogenetic techniques to advance their studies. The depth of knowledge and diverse expertise of the CYT staff provides an invaluable resource to investigators looking to move their research forward. Comprehensive cytogenetic and molecular cytogenetic testing and interpretation is not offered in any other core or research laboratory at Mayo Clinic. It is the CYT's deep commitment to working with the investigator to meet their unique scientific needs that enables the CYT to continue to be an invaluable resource to Mayo Clinic Cancer Center members.